Marine interests on the Big Island (leeward/southeast coasts) should finalize all preparations for deteriorating conditions by noon Wednesday as Hurricane Lane begins to approach from the south. The earliest potential onset of tropical storm force winds (34 knots or greater) across the waters around South Point and off the coast of Kona will be through the day Wednesday. Once these conditions are realized, it will be too late to prepare. Interests in Maui County and on Oahu should finalize all preparations come Wednesday evening and by noon Thursday for Kauai.

The Hurricane Watch currently in place for the waters surrounding Oahu and Maui County will likely become updated to a warning later Wednesday and expanded across the Kauai waters.

Impacts associated with Lane through the rest of the week for the islands will include: hazardous seas, life-threatening surf (warning level), beach erosion, overwash onto vulnerable coastal roadways, and storm surge along exposed coasts/harbors of all islands as Lane passes through.

Improving conditions are expected by the end of the upcoming weekend as Lane slowly begins to track away from the island waters.

Tide Predictions

Low tide at Kahului was 0.14 foot at 2:00 PM early this afternoon, rising to a high of 2.37 foot at 2:00 PM early this afternoon, then dropping to a low of 0.87 foot at 2:00 PM early this afternoon.

The sunrise was at 06:06 am this morning and will set at 06:50 pm this evening. The Moon is currently 11 days old, and is in a Waxing Gibbous phase. The next Full Moon will occur at 11:58 AM on Sunday, August 26th.

Maui Weather

°/°

Wind: n/a at 0 mph

Sunrise: Sunset:

current observations as of 2am May 25th, 2019

Weather Outlook for Wednesday, 22nd August 2018

Summary

A strong high pressure ridge far to the north of the Hawaiian Islands will produce breezy winds over the local area ahead of Hurricane Lane. Deep tropical moisture will move up from the south with Lane, spreading increasing rain shower bands and possible thunderstorms over the Big Island by Wednesday morning and reaching Maui by Wednesday afternoon and evening. These shower bands will continue to spread northward across the rest of the state as Lane moves northward. Hurricane Lane will bring damaging winds, dangerous surf, and intense flooding rains to areas within the state of Hawaii from Wednesday through Saturday.

Detailed Discussion

Please note that tropical cyclone operations are in effect. To incorporate the latest forecast information from the Central Pacific Hurricane Center (CPHC), public forecast updates from the Honolulu Forecast Office will be delayed to immediately follow the latest forecast package from CPHC.

Tranquil weather conditions across the islands today will become more unsettled and threatening over the next several days as Lane a category 5 Hurricane roughly 370 miles south-southeast of Kona moves northwestward into the Hawaiian Islands. Lane is one of the strongest storms to ever move into the Hawaiian Islands and the current forecast track will bring local impacts of damaging winds and life threatening flooding rain across the state from Wednesday through Saturday. Do not wait until the storm reaches your island, the time to prepare for hurricane impacts is now.

As Hurricane Lane moves further northward, deep unstable tropical moisture will spread across the region. Precipitable Water (PW) values will range from 2.0 to 2.5 inches, producing hot and humid weather conditions and widespread convective heavy rain shower bands. This extremely deep moisture will reach the Big Island by Wed morning, Maui county by Wed night, Oahu by Thursday, and Kauai by later Thursday or Thursday night. Once this extreme moisture arrives the heavy rainfall will start to develop quickly with the orographic effects from mountain ranges alone causing flooding threats across the islands with additional forcing from an upper level trough just to the northwest of the islands.

Strong winds will develop, based on the latest CPHC forecast, starting over the Big Island as soon as Wednesday afternoon with hurricane force winds developing by Wednesday night. The highest wind threat for the Big Island will start along the western side as strong and gusty down slope winds interact with mountainous terrain. On Maui county, damaging tropical storm force winds could begin as early as late Wednesday night, with dangerous hurricane force winds possible starting on Thursday. Oahu could see damaging winds by Thursday morning, and Kauai by Thursday night. Hurricane Watches could be needed for other areas as Lane draws closer.

It’s not possible to know which islands will see the worst storm effects right now. The CPHC forecasts continue to show that all islands are at risk from direct effects from the core of Hurricane Lane. Everyone should take this hurricane very seriously and should prepare accordingly. It’s also important to expect that there will need to be future adjustments to the track and intensity forecast, particularly with the challenging recurvature forecast that Lane is presenting. Prepare for the worst and hope for the best.

The combination of a deep moist unstable layer and strong low level wind shear along and to the east of the track of Lane will make tornadoes and large waterspouts a distinct possibility in the rainbands across the right semicircle of the hurricane. These continue to be included in the TCV and HLS products as an elevated threat from Oahu to the Big Island. Will be able to better refine the threat as Lane approaches.

There is a considerable amount of uncertainty in the models as to when the deep moisture in the wake of Lane departs. The ECMWF shows some modest drying out over the weekend, while the GFS and to a lesser extent the NAVGEM maintain high PW over the islands into next week, which could be troublesome on any areas that get excessive rainfall. There may also be some lingering support from upper troughing to the NW.

Leeward West (Lahaina, Ka`anapali):

HURRICANE WATCH IN EFFECT… …FLASH FLOOD WATCH IN EFFECT FROM 6 AM HST THIS MORNING THROUGH
FRIDAY AFTERNOON……HIGH SURF ADVISORY IN EFFECT FROM NOON TODAY TO 6 AM HST
THURSDAY. Breezy. Mostly sunny with isolated showers early in the morning, then partly sunny with scattered showers in the late morning and afternoon. Highs 83 to 90. Northeast winds 15 to 20 mph. Chance of rain 50 percent.

Windward West (Wailuku, Waiehu):

HURRICANE WATCH IN EFFECT……FLASH FLOOD WATCH IN EFFECT FROM 6 AM HST THIS MORNING THROUGH
FRIDAY AFTERNOON. Mostly cloudy. Breezy. Scattered showers early in the morning, then showers likely in the late morning and afternoon. Highs 69 to 87. Northeast winds 15 to 20 mph. Chance of rain 70 percent.

Windard Haleakala (Hana, Haiku, Makawao):

HURRICANE WATCH IN EFFECT……FLASH FLOOD WATCH IN EFFECT FROM 6 AM HST THIS MORNING THROUGH
FRIDAY AFTERNOON. Mostly cloudy. Breezy. Showers likely in the morning, then occasional showers in the afternoon. Highs around 84 at the shore to around 71 at 5000 feet. East winds 15 to 20 mph. Chance of rain 90 percent.

Leeward Haleakala (Kihei, Wailea, Makena):

HURRICANE WATCH IN EFFECT……FLASH FLOOD WATCH IN EFFECT FROM 6 AM HST THIS MORNING THROUGH
FRIDAY AFTERNOON……HIGH SURF ADVISORY IN EFFECT FROM NOON TODAY TO 6 AM HST THURSDAY. Mostly sunny in the morning then becoming partly sunny. Breezy. Isolated showers. Highs around 90 at the shore to 71 to 78 upcountry. East winds 10 to 20 mph. Chance of rain 20 percent.

Haleakala Summit

HURRICANE WATCH IN EFFECT……FLASH FLOOD WATCH IN EFFECT FROM 6 AM HST THIS MORNING THROUGH
FRIDAY AFTERNOON. Mostly sunny. Breezy. Isolated showers early in the morning, then scattered showers in the late morning and afternoon. Highs around 60 at the visitor center to around 56 at the summit. East winds 15 to 20 mph. Chance of rain 50 percent.